User manual, system overview and operating procedures for the Solar-Tracking Radiometry Platform (So-Rad) by Plymouth Marine Laboratory. The purpose of the Solar-tracking Radiometry platform (So-Rad) is to maintain optimal viewing angles of radiance sensors recording water-leaving reflectance, avoiding sun glint and platform shading even when deploying from moving platforms such as ships or buoys. So-Rad is developed to operate autonomously, with low power consumption, integrating commercially available (ir)radiance sensors and providing remote connectivity. Following initial configuration, So-Rad will determine when measurement conditions are met to trigger the connected sensors at set intervals, store the sensor response and metadata, and communicate these to a centralized repository when a data connection is available.